Publications by authors named "A Vaksmaa"

Large quantities of plastic enter the oceans each year providing extensive attachment surfaces for marine microbes yet understanding their interactions and colonization of plastic debris remains limited. We investigated microbial colonization of various plastic types (polyethylene, polystyrene, polyethylene-terephthalate, and nylon) in ex-situ incubation experiments. Plastic films, both UV-pretreated and untreated, were exposed to seawater from a coastal and an offshore location in the North Sea.

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Plastic pollution in the marine realm is a severe environmental problem. Nevertheless, plastic may also serve as a potential carbon and energy source for microbes, yet the contribution of marine microbes, especially marine fungi to plastic degradation is not well constrained. We isolated the fungus Parengyodontium album from floating plastic debris in the North Pacific Subtropical Gyre and measured fungal-mediated mineralization rates (conversion to CO) of polyethylene (PE) by applying stable isotope probing assays with C-PE over 9 days of incubation.

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Ocean plastic pollution is a severe environmental problem but most of the plastic that has been released to the ocean since the 1950s is unaccounted for. Although fungal degradation of marine plastics has been suggested as a potential sink mechanism, unambiguous proof of plastic degradation by marine fungi, or other microbes, is scarce. Here we applied stable isotope tracing assays with C-labeled polyethylene to measure biodegradation rates and to trace the incorporation of plastic-derived carbon into individual cells of the yeast Rhodotorula mucilaginosa, which we isolated from the marine environment.

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Ocean plastic pollution is a problem of increasing magnitude; yet, the amount of plastic at the sea surface is much lower than expected. Solar ultraviolet (UV) radiation can induce photodegradation, but its importance in determining the longevity of floating plastic remains unconstrained. Here, we measured photodegradation rates of different plastic types slightly larger than microplastics (virgin polymers and floating plastic debris) under simulated marine conditions.

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